Fluorinated compounds containing functional groups

ABSTRACT

GROUPS ATTACHED TO THE OLIGOMER RESIDUE. Derivatives containing the first three of these groups are made by contacting an oligomer with anhydrous gaseous ammonia in a solvent medium or by heating with a concentrated aqueous solution of ammonia. Those containing NHNH2 groups are made by reactions between oligomer and hydrazine. The derivatives may be converted into highly fluorinated nitriles which can be reduced to amines and quaternised with alkyl halides to yield cationic surfactants.   Derivatives of oligomers of tetrafluoroethylene and of hexafluoropropene, contain one or more

United States Patent [191 Fielding FLUORINATED COMPOUNDS CONTAINING FUNCTIONAL GROUPS [75] Inventor: Harold Crosbie Fielding, Northwich,

England [73] Assignee: Imperial Chemical Industries Limited, London, England [22] Filed: July 31, 1969 [21] Appl. No.: 870,788

Related U.S. Application Data [62] Division of Ser. No. 656,682, July 28, 1967, Pat. No.

[30] Foreign Application Priority Data Aug. 24, 1967 Great Britain 36,862/67 [52] U.S. Cl... 260/465.5 R, 260/566 D, 260/583 B,

260/583 66 [51] Int. Cl. C07c 121/02, C07c 121/42 [58] Field of Search 260/465.7, 465.5, 260/583 GG, 583 B [56] References Cited UNITED STATES PATENTS 3,502,726 3/1970 Fielding 260/583 2,998,425 8/1961 Dickinson, Jr. et aL. 260/465.5 R X June 26, 1973 3,121,108 2/1964 Josey et a]. 260/465.5 R X 3,475,481 10/1969 Krespan 260/465.5 3,194,840 7/1965 Berry 260/465.7 X 3,234,267 2/1966 Vogli 260/465.7 3,326,976 6/1967 Middleton... 260/583 66 3,546,276 12/1970 Gale 260/465.5 R X Primary Examiner-Joseph P. Brust Attorney-Cushman, Darby & Cushman [57] ABSTRACT Derivatives of oligomers of tetrafluoroethylene and of hexafluoropropene, contain one or more 4 Claims, No Drawings FLUORINATED COMPOUNDS CONTAINING FUNCTIONAL GROUPS This is a division of application Ser. No. 656,682, filed July 28, 1967.

BACKGROUND OF THE INVENTION 1. Field of the Invention Reactions of oligomers of tetrafluoroethylene and of hexafluoropropene with inorganic nucleophiles whereby one or more fluorine atoms are eliminated from the oligomer molecule.

2. Description of Prior Art Nothing pertinent known.

SUMMARY OF THE INVENTION Novel derivatives of oligomers of tetrafluoroethylene and of oligomers of hexafluoropropene whose mlecules contain one or more CEN.

groups in which the carbon atoms are carbon atoms of the oligomers. Those derivatives containing -C l N.

M... H \C=NH or (|JNH2 groups are made by reactions between oligomer and ammonia, whilst those containing groups arise from reactions of oligomer with hydrazine.

This invention relates to highly fluorinated compounds containing functional groups, particularly to nitrogen-containing compounds derived from oligomers of tetrafluoroethylene and of hexafluoropropene.

Oligomers of tetrafluoroethylene are for the purpose of this specification defined as branched chain internally unsaturated perfluoroolefins having the empirical formula (C F where n is an integer greater than 3 and commonly from 4 to 7, though it can be greater. Likewise oligomers of hexafluoropropene are defined as branched-chain internally unsaturated perfluoroolefins having the empirical formula (C F where n is 2 or 3. These oligomers can be made by heating respectively tetrafluoroethylene or hexafluoropropene with an ionic catalyst, for example an alkali metal halide, in a polar organic solvent, for example dimethylformamide.

Some of the fluorine atoms in an oligomer molecule can be removed by reactions between the oligomer and compounds containing reactive atoms, for example hydrogen or alkali metal atoms, whereby derivatives of the oligomer are formed. Those containing functional groups possess useful surface-active and other proper-- 6 zine residues become linked through one or more nitrogen atoms. The courses of the reactions are not simple since fluorine atoms attached to more than one carbon atom of the oligomer can be eliminated, but it can be said that in general ammonia reacts with a -CF I group to introduce a 10 group into the oligomer molecule; with a group to introduce a r \C=NH group and with a -CF group to introduce-a -C a N group. Hydrazine reacts in a similar manner with a group to introduce a group into the oligomer molecule.

Thus the invention in its general form provides highly fluorinated nitrogen-containing derivatives of oligomers of tetrafluoroethylene and of oligomers of hexafluoropropene whose molecules contain at least one of the groups GEN. \CZNII, )NIIz and ONNNH2 in which the carbon atoms are carbon atoms of the oligomer molecule.

In a particular form the invention provides highly fluorinated nitrogen-containing derivatives of tetrafluoroethylene tetramer (C 2F having respectively the empirical formulae C F NH and C F, (NI-I) and the highly fluorinated nitrogen-containing derivative of tetrafluoroethylene pentamer (C F having the empirical formula C9Fw(NH )(CN).

The derivatives obtained by reactions of ammonia with the tetramer and pentamer of tetrafluoroethylene and of hydrazine with the pentamer are well character- 50 ised and their properties are consistent with the structural formulae described hereinafter. Reactions of ammonia and-hydrazine with higher oligomers of tetrafluoroethylene, for example the hexamer, and of ammonia with the isomeric trimers of hexafluoropropene give rise to derivatives containing one or more of the groups -CN.

\CNH, o N112 and (l NH-NH but it is not yet possible to say anything more specific about their molecular structures.

The reactions between oligomers and ammonia can conveniently be carried out at 10 C to 30 C by bubbling gaseous ammonia into a stirred solution of the oligomer in an inert solvent, for example ether or 1,1 ,2- trifluoro-l,2,2-trichloroethane or in a diluent such as benzene in which the product dissolves. The reactions can also be carried out in the absence of a solvent, but precipitated solids may then make stirring difficult. The reactions can also be carried out at higher temperatures, for example 50 C to 100 C, under moderate pressure if desired, using a strong aqueous solution of ammonia and stirring vigorously.

The derivatives obtained by reactions of oligomers with ammonia and hydrazine are useful intermediates. For example they can be hydrolysed with aqueous solutions of caustic soda or caustic potash to give highly flu orinated nitriles that can be reduced to amines and quaternised, for example with methyl iodide, to give cationic surfaceactive agents.

EXAMPLE 1 Anhydrous ammonia was bubbled through a stirred solution of tetrafluoroethylene pentamer (100 g.) in ether (1 litre) at room temperature. When the reaction was complete the precipitated ammonium fluoride was filtered off and the ether solution evaporated to give an off white solid. Recrystallisation from benzene gave plates having a m.pt. 69 C in a yield of 80 g.

Found by analysis C, 26.1 H, 0.8: F, 67.4, N, 6.4 percent by weight.

C F l-l N requires C, 26.4; H, 0.4; F, 67.0; N, 6.2 percent by weight.

The infra-red spectra showed the presence of both -C E N and NH groups and mass-spectrographic analysis indicated a molecular formula CmFmHzNg. F nuclear magnetic resonance measurements showed two equivalent C 1 groups and two different CFg groups. This evidence taken as a whole is consistent with the structural formula (C2F5 )2(CF3)C.C(CN)= a) H2- EXAMPLE 2 The second component was shown by elementary analysis and mass-spectrographic analysis to have the empirical formula CgFrgNgHg. F nuclear magnetic resonance measurements were consistent with the structural formula EXAMPLE 3 Anhydrous ammonia was bubbled through a solution of 50 g. tetrafluoroethylene hexamer, (C Fn mixed isomers, in 100 mls of l,l,2-trifluoro-l,2,2- trichloroethane at room temperature. When the reaction was complete the precipitated ammonium fluoride was filtered off and the solution evaporated to dryness to give a white solid of indefinite melting point. lts infra red spectra indicated the presence of a -C N and an NH, group.

EXAMPLE 4 Tetrafluoroethylene pentamer (50 g.) and aqueous ammonia (50 mls of solution of specific gravity 0.880) were heated together under reflux at C with vigorous stirring for two hours. The reaction mixture was cooled and filtered to give 15 g. of a white solid which on recrystallisation from benzene melted at 68 C-69 C and was identified as the same compound as that described in Example 1.

EXAMPLE 5 Tetrafluoroethylene pentamer, (C F,) (12 g.) was added to a stirred solution of hydrazine hydrate (42 g.) in water (30 mls)/ethanol mls). An exothermic reaction set in immediately and the reaction mixture turned green. lt was left under reflux for two hours after which mls water was added and the mixture extracted with ether (4 X 75 mls). The ether extract was dried over anhydrous magnesium sulphate and distilled to remove ether and ethanol. The residue solidified on cooling and on recrystallisation from benzene gave 1.5 g. (l2 percent yield) of white crystals melting at 70 C-7l C. Found by analysis percent by weight. C F N H requires C, 23.4; H, 0.59; N, 5.45; F, 70.5 percent by weight.

The mass spectrum agreed with this empirical formula and F' nuclear magneticresonance measurements were consistent with the structural formula (C F (CF )C.C(CF )=C(CF )NHNH EXAMPLE 6 The ipfra-redspectra of the compoundshowed it to contain a -C N and an NH group.

EXAMPLE 7 The reaction described in Example 6 was carried out with another of the three isomeric trimers of hexafluoropropene, namely perfluoro-2,3,S-trimethylhexene-2, at a temperature of 45 C. The product after recrystallisation from toluene/ether melted at Cl 27 C with some decomposition. lts infra-red spectra showed it to contain a C E N. and an=NH group.

What we claim is:

1. A highly fluorinatecl nitrogen-containing derivative of tetrafluoroethylene pentamer having the formula (C2F5)2 2. A process for making branch chain internally unsaturated compounds consisting essentially of reacting at a temperature of 10 to 100 C anhydrous ammonia with an oligomer of tetrafluoroethylene having the empirical formula (C F,),, where n is 3 to 7 or hexafluoropropene having the empirical formula (C F where n is 2 or 3.

3. The process of claim 2 in which the oligomers are selected from the group consisting of the tetramer C F pentamer c oFgo and the hexamers C E- of tetrafluoroethylene and the trimers C F of hexafluoropropene.

4. A process according to claim 2 in which the reaction is carried out at a temperature of 10 C to 30 C. i i

C, 24.9; H, 0.48; N, 6.4; F, 66.7 

2. A process for making branch chain internally unsaturated compounds consisting essentially of reacting at a temperature of 10* to 100* C anhydrous ammonia with an oligomer of tetrafluoroethylene having the empirical formula (C2F4)n where n is 3 to 7 or hexafluoropropene having the empirical formula (C3F6)n where n is 2 or
 3. 3. The process of claim 2 in which the oligomers are selected from the group consisting of the tetramer C8F16, pentamer C10F20 and the hexamers C12F24 of tetrafluoroethylene and the trimers C9F18 of hexafluoropropene.
 4. A process according to claim 2 in which the reaction is carried out at a temperature of 10* C to 30* C. 